onesignal service push notifications
we use the notficiation services which is served by onesignal
on client side usage: https://documentation.onesignal.com/docs/web-push-sdk
as shown below. we just need following ambigious three fields then we might be able to test whether or not class works
require 'CURL.php';
require 'OneSignal.php';
$oneSignal = new OneSignal(APP_ID, API_KEY,AUTH_TOKEN);
ECHO $oneSignal->viewNotifications(2,5);